This invention relates to a drying device for a vehicle washing apparatus and more particularly to a link mechanism for supporting a top drying nozzle suspended from an inverted U-shaped frame member.
In general, a vehicle washing apparatus has an inverted U-shaped frame member movable along a pair of rails between which a vehicle to be washed is parked. The frame member comprises two side frames disposed vertically and a top frame disposed horizontally. Inside the side frames are rotatably provided two side brushes, and under the top frame is rotatably provided a top brush. There is also provided a water spray device in the frame member. With those brushes being rotated and the water spray device being operated, the frame member is moved along the rails to wash the body of the vehicle.
In addition, the vehicle washing apparatus has also a drying device for blowing air against the body of the vehicle in order to blow off water drops left on the body after the body has been washed by the water spray device. The drying device comprises a pair of side nozzles which are fixed to the side frames of the inverted U-shaped frame member and a top nozzle which is held on the top frame thereof so as to be moved upward and downward in accordance with the height of the vehicle to be washed and the configuration of the top surface thereof.
Such a drying device is disclosed in Japanese Utility Model Publication No. 24386/1981. In this Publication, the top nozzle of the drying device is supported at the lower portion of a link which is pivotably held by a vertical arm fixed to the top frame of an inverted U-shaped frame member. A driving cylinder is provided, in the frame member, for swinging the link upward and downward in accordance with the configuration of the top surface of a vehicle to be washed.
In such a link mechanism, it is unavoidable that the position of the top nozzle is changed in the backward and forward directions when the link is swung to raise and lower the top nozzle in accordance with the configuration thereof.
In drying in such a manner that water drops left on the surface of the body of the vehicle are blown off by the drying device to finish the washing operation, the top nozzle must be moved ahead of the two side nozzles to blow off the water drops completely, because some of the water drops on the top surface thereof are dropped along the side surfaces of the vehicle body, and the water drops dripping along the side surfaces thereof have to be blown off by the side nozzles following the movement of the top nozzle. If the top nozzle is moved following the side nozzles, the water drops blown off by the top nozzle drip along a region of the side surfaces thereof against which air has already been blown by the side nozzles thereby to leave the water drops on the side surfaces.
In the top nozzle of the above conventional drying device, as the top nozzle is moved backward and forward when the link for supporting the top nozzle is swung to raise and lower it in accordance with the configuration of the top surface thereof, the top nozzle cannot be always placed ahead of the side nozzles. If the top nozzle is placed far ahead of the side nozzles to always keep the top nozzle located ahead of the side nozzles, the width of the top frame for supporting the top nozzle has to be great thereby making the frame member bulky.
To solve this problem, Japanese Utility Model Publication No. 2683/1983 discloses a drying device in which a top nozzle and a pair of side nozzles are integrated with each other to form an integrated nozzle unit supported by an inverted U-shaped frame member so as to be moved upward and downward. The integrated nozzle unit is raised and lowered by a winch mechanism. However, the winch mechanism is relatively complicated.